First of all we would like to say thanks to our users who gave us feedback and reported bugs. We really appreciate your help!
Below is the list of updates included to the Release 0.4.6:

Features:
– PostgreSQL psycopg2 driver support. Previously Pony supported only PyGreSQL driver. Now you can use

    db = Database('postgres', ...)

for psycopg2 driver and

    db = Database('pygresql', ...)

for PyGreSQL driver

– Integration with Bottle web framework

Bug fixes:
– MySQL should CONCAT(a, b) instead of a || b for string concatenation
– MySQL TRIM/LTRIM/RTRIM bug fixed
– PostgreSQL count(distinct(column1, column2)) works incorrectly if any of columns is null
– least(a, b, c) and greatest(a, b, c) are used instead of min(a, b, c) and max(a, b, c) in all dbproviders except sqlite
– GitHub #1 – Typo in regex
– GitHub #6 – Query results cache was not cleared after commit
– Aggregation bug fixed (unnecessary joins were removed)
– Use ‘power’ function for all db providers instead of ‘**’
– Collection attributes cannot be used for ordering
– Numerous small bugs were fixed

Enhancements:
– Common Database Pool implementation added to dbapiprovider module
– Numerous optimizations and refactorings